Do you mean tight all over as in the whole garment? if so you need a bigger cag. The necks are usually designed to be trimmed as are the cuffs.
I have trimmed my paddle pants on the ankle's, my storm cag on the neck and cuffs and I have also trimmed my dry suit neck, it's normal to do this as long as the garment is designed for it.
EDIT: Taken from up and under store. "The Nookie Extreme Cag is one of the better cags on the market. Great attention to detail makes it one of the best-suited cags to British paddling.
The full dry cag has latex seals on the neck and wrists with a neoprene outer cuff for protection and there is a double waist tube with Little Braces inside to hold the deck up. For added durability they have made the outside of the arms and cuffs with a tough cordura. There is even a ring of cordura between the neck seal and the rest of the cag. Bombproof!
The first thing that you notice when you put this cag on is how comfortable it is and that the articulated arms make a world of difference. After many trips on the local rivers and surf the cag has kept me dry, no matter how many times waves break on your head or you roll back up. You may need to trim the latex seal down to size, but remember that latex will stretch and soften slightly so be careful not to cut too much off."